Difference Between Adsorb vs Absorb

These two similar-sounding processes are often confused with one another based on both their spelling and sound. But the difference between adsorb vs absorb is actually quite significant as we will shortly discover.

By the time you have read through this article, you will no longer have any confusion over their individual meanings and will be able to use them both fluently. Read on for everything you need to know about these similar-sounding words.

Definition of Adsorb

To adsorb is to have molecules or atoms from a gas, liquid, or solid form together to create a thin film on an exterior or interior surface. You have seen adsorption in action as part of your everyday life probably without ever realising exactly what it was. Common examples can be seen absolutely everywhere you turn whether it is in your bathroom, on your walls, or in the corner of your shed.

If you have ever seen mould collected in the corner of a room or limescale building up on a wall or even bacteria forming on the surface of the wood in your shed, these are classic cases that serve to effectively highlight the difference between adsorption and absorption in practical action.

When something adsorbs, it quite literally clings to the surface of something and forms a visible layer, one that we can easily see. We can also freely access the contents of the adsorption layer with touch and identify that it is clearly different from the surface beneath.

This serves as a stark contrast to absorption, which is a very internal process. When something absorbs it enters into the body of something else and becomes a part of the whole. You cannot then remove it with touch or clearly see how it separates.

Definition of Absorb

Absorption is to internalise something or soak it up via a chemical or physical process or mechanism of action. Immediately, the above description reveals that this particular process is an internal one, which greatly helps us to distinguish a clear variation between adsorption vs absorption.

When something absorbs, it quite literally enters into and becomes a part of the main body of something else. A good example would be a powder being mixed with a liquid. The powder then becomes a part of the liquid and fails to be distinguishable as a separate entity any longer.

You can clearly see how something that adsorbs is different from the surface to which it has adsorbed. When something absorbs, you cannot clearly define the unique structure of the original substance that first got introduced into the absorption process.

Referencing powder again, if a powder were to adsorb onto a surface, this would mean that you could scratch it away with your finger. If a powder were introduced to a liquid to be absorbed, however, you would not be able to separate it or see it in its original form anymore.

Our upcoming quick reference table will help you to clearly identify the two.

Main Differences Between Adsorb vs Absorb

The quick reference table below provides an accessible visual reference for you to make use of anytime you find yourself confused about this subject and in need of a quick refresh.

Basis of Comparison	Adsorb	Absorb
Where does it take place	Externally	Internally
Is the base substance still visible	Yes	No
Can you touch the substance after the process has taken place	Yes, the original substance is still visible and can be touched.	No, the original substance has become part of another substance.
Temperature	Adsorption usually takes place at lower temperatures.	Temperature has no impact on absorption.
Process speed	Increases at first but then decreases	Takes place at one speed

These key points form the majority of the basis for allowing us to separate adsorb vs absorb.

Difference Between Adsorb and Absorb: Conclusion

You should now have a clearer understanding of what these two words mean and the unique processes behind each. Just remember that absorption means that something enters into something else, and adsorption means that something clings onto the surface of something else. This difference between exterior and interior is where we find the critical variation between these processes.